Originally Posted by JemyM
"The currently active display driver is not compatible with nHancer. Only nVidia Forceware versions 6x.xx and later are supported!"
Im using 97.44_forceware_winxp_international.exe with two 8800gtx
I have exactly the same configuration...
I guess the driver installation wasn't finished correctly.
You should try to uninstall the driver (using "Add/Remove software"). Reboot. Reinstall the driver. Reboot once again. Then it should work.